摘要
We present algorithms revealing new families of polynomials admitting sub-exponential detection of -adic rational roots, relative to the sparse encoding. For instance, we prove -completeness for the case of honest -variate -nomials and, for certain special cases with exceeding the Newton polytope volume, constant-time complexity. Furthermore, using the theory of linear forms in -adic logarithms, we prove that the case of trinomials in one variable can be done in . The best previous complexity upper bounds for all these problems were or worse. Finally, we prove that detecting -adic rational roots for sparse polynomials in one variable is -hard with respect to randomized reductions. The last proof makes use of an efficient construction of primes in certain arithmetic progressions. The smallest where detecting -adic rational roots for -variate sparse polynomials is -hard appears to have been unknown.